[Pw_forum] symmetry operation not allowed

[Axel Kohlmeyer]

On Fri, 18 Apr 2008, Lily Anh wrote:

LA> Thanks for your suggestion.
LA> I have changed ecutwfc (from 20-50Ry every 5 Ry), ecutrho (200-1200 
LA> every 50), k grid. But nothing works. How to change nr1 nr2 nr3, 
LA> larger or smaller?

lily,

as stefano wrote, you are trying to solve the wrong problem!
your input coordinates are only near symmetric. symmetrize
them and _then_ adjust the grid, if you still see warnings.

for that you have to keep in mind that the values chosen by
the program are always the smallest possible (i.e. supported
by the fast fourier transform library), so you have to increase
them (at additional computational cost!) to make them match
the symmetry of your system.

cheers,
   axel.


-- 
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Axel Kohlmeyer   akohlmey at cmm.chem.upenn.edu   http://www.cmm.upenn.edu
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